JPH0616454B2 - Multiple cylindrical winding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention is used as a winding wire of an induction electric device such as a transformer or a reactor, and particularly relates to a multiple cylindrical winding wire in which potential oscillation is suppressed to a small level. .

(Prior art) Multiple cylindrical windings used as windings for induction electric equipment such as transformers and reactors have a large facing area between winding layers and a small number of winding layers, resulting in large series capacitance. It has the characteristic that the potential oscillation inside is small. Therefore, it is mainly used for high voltage windings in inner iron transformers.

FIG. 4 is a sectional view showing such a conventional multiple cylindrical winding. The structure of the conventional multiple cylindrical winding is as follows. First, a conductor is cylindrically wound on the innermost interlayer insulating paper 1a made of kraft paper to form a first layer cylindrical winding 2a. Next, a cooling oil passage 3a is provided around the outside of the cylindrical winding 2a by a duct piece or the like. The interlayer insulating paper 1b is wound around the outside of the cooling oil passage 3a again, and the interlayer insulating paper 1b is further wound.
The second layer of cylindrical winding 2b is wound on the outer side of. In this way, a plurality of interlayer insulating papers 1a, 1b ...
b, ..., Cooling oil passages 3a, 3b ,. The end portions of the respective layers of the cylindrical windings 2a and 2b are connected alternately in the upper and lower portions and connected in series. The multiple cylindrical winding has a line end shield 4 provided on the outermost cooling oil passage 3e to increase the series capacitance. The thickness of the inter-layer insulating papers 1a, 1b, ... Is thin because no voltage is applied on the connection end side of the cylindrical winding, and two layers of voltage are applied on the opposite end side, which is not connected, so that it is thicker. The cross section is tapered.

However, the conventional multi-cylinder winding as described above has the following drawbacks. That is, as can be seen from the cross-sectional view of FIG. 4, since the line-end shield 4 occupies a large space-wise ratio in the entire winding, the space factor of the winding is reduced, resulting in a transformer. Becomes larger. If the line-end shield 4 is omitted, the electrostatic capacitance existing between the outermost cylindrical winding 2e and the line-end shield 4 becomes zero, and the series capacitance of the winding becomes small. The potential vibration becomes large and the insulation performance at the time of lightning impulse intrusion deteriorates. In order to prevent this, the dimensions of the cooling oil passages 3a, 3b, ... Between the respective layers may be enlarged, but if this is done, the space factor of the windings will also decrease and the transformer will become larger.

As described above, in the conventional multi-cylindrical winding, the space factor of the winding is low, which has been a big problem in realizing the downsizing and high efficiency of the transformer which has been particularly demanded recently.

The present invention has been made to solve the above problems, and it is an object of the present invention to obtain a multiple cylindrical winding in which the space factor of the winding is improved, the device is downsized, and the efficiency is improved. To aim.

Structure of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention is a coil of at least one or more cylindrical windings including an outermost cylindrical winding of multiple cylindrical windings. A shield conductor is wound around a plurality of places between the conductors at least once, and at least one end of the shield conductor is connected to a coil conductor or another shield conductor.

(Operation) With this, capacitance is added between the shield conductor and the cylindrical winding, the series capacitance of the outermost cylindrical winding is increased, and potential oscillation is suppressed.

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying drawings by assigning the same reference numerals to the same portions as those of the conventional one. In FIG. 1, first, a conductor is wound in a cylindrical shape on the innermost interlayer insulating paper 1a made of kraft paper to form a first layer cylindrical winding 2a. Next, a cooling oil passage 3a is provided around the outside of the cylindrical winding 2a by a duct piece or the like. The interlayer insulating paper 1b is wound again on the outside of the cooling oil passage 3a, and the second-layer cylindrical winding 2b is wound on the outside of the interlayer insulating paper 1b again. In this way, a plurality of interlayer insulating papers 1a, 1b, ...
b, ..., Cooling oil passages 3a, 3b ,. The end portions of the respective layers of the cylindrical windings 2a and 2b are connected alternately in the upper and lower portions and connected in series. The multiple cylindrical winding has a line end shield 4 provided on the outermost cooling oil passage 3e to increase the series capacitance. The thickness of the inter-layer insulating papers 1a, 1b, ... Is thin because no voltage is applied on the connection end side of the cylindrical winding, and two layers of voltage are applied on the opposite end side, which is not connected, so that it is thicker. The cross section is tapered. Further, shield conductors 101, 102, which are insulated and coated between the upper, middle, and lower coil conductors near the line terminal U of the outermost cylindrical winding 2e,
103 is separately wound one turn each. FIG. 2 shows the connection relationship of these windings. That is, the cylindrical windings 2a, 2b, ... 2e are sequentially connected in series so that one end of the innermost cylindrical winding 2a becomes the neutral point terminal 0 and one end of the outermost cylindrical winding 2e becomes the line terminal U. One high voltage winding is configured as a whole. Also, the cylindrical winding 2e
One end of the shield conductor wound in the middle stage is connected to the line terminal U of the cylindrical winding, and the other end is opened in the cylindrical winding 2e. Further, one end of the shield conductor 101 wound on the upper stage of the cylindrical winding 2e and one end of the shield conductor 103 wound on the lower stage are connected by a crossover wire 20, and the other ends are opened inside the cylindrical winding 2e. There is.

According to the multiple cylinder winding of the present invention configured as described above,
Shield conductor 1 wound in the outermost cylindrical winding 2e
01, 102 and 103 are capacitively coupled to the adjacent coil conductors. This shield conductor 10
Since 1, 102 and 103 are connected as shown in FIG. 2, the outermost cylindrical winding 2e is taken out and an equivalent circuit is drawn as shown in FIG. In FIG. 3, 2eu, 2
el represents a line end side upper stage and a neutral point side lower stage of the cylindrical winding 2e, respectively, and Ct represents shield conductors 101, 102,
It represents the capacitance between 103 and the adjacent coil conductor. As can be seen from FIG. 3, the shield conductors 101, 1
The capacitance between 02 and 103 and the coil conductor will increase the series capacitance of the cylindrical winding. The size of this capacitance is determined by the coil diameter, bit, conductor insulation thickness, etc., but the conductor insulation thickness is much smaller than the cooling oil passage between the windings, and the dielectric constant of the conductor insulation. Is larger than the dielectric constant of the insulating oil, it can be easily made to have the same size as the capacitance added by the line-end shield in the conventional cylindrical winding. Therefore, it is possible to obtain a sufficient series capacitance of the cylindrical winding without the line-end shield as in the past, to suppress the potential oscillation when applying an impulse voltage, improve the insulation characteristics, and downsize the device. You can

Furthermore, in the present invention, when a so-called composite conductor in which conductors that have been subdivided as the shield conductor and separately insulated are collectively insulated is used, the eddy current loss that occurs in the shield conductor can be reduced, so Small,
It is possible to obtain a multi-cylindrical winding with low loss. Also, the shield conductor of the present invention can be wound around at least one or more cylindrical windings including the outermost cylindrical winding.

[Advantages of the Invention] As described above, according to the present invention, the cylindrical windings having a plurality of layers wound in the coaxial cylindrical shape are adjacent to each other via the interlayer insulating paper and the cooling oil passage. , In a multi-cylinder winding in which the whole is connected in series, the shield conductor is wound at least once at a plurality of positions between the coil conductors of at least one or more cylindrical windings including the outermost cylindrical winding, At least one end of the conductor is connected to a coil conductor or another shield conductor, and the space factor of the winding is improved, and the equipment is downsized and the efficiency is improved. Can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG.
FIG. 3 is a front view showing the connection relation of the windings in the figure, FIG. 3 is an equivalent circuit diagram of the outermost cylindrical winding, and FIG. 4 is a sectional view showing a conventional cylindrical winding. 1a, 1b ... interlayer insulation paper, 2a, 2b, 2e ... cylindrical winding, 3a, 3b ... cooling oil passage, 101, 102, 10
3 ... Shield conductor.

Claims (2)

[Claims] 1. A multi-cylinder winding in which a plurality of layers of cylindrical winding wound coaxially through an interlayer insulating paper and a cooling oil passage are connected alternately adjacent to each other in an upper and lower direction and the whole is connected in series. In the wire, the shield conductor is wound at least once or more at a plurality of positions between the coil conductors of at least one cylindrical winding including the outermost cylindrical winding, and at least one end of the shield conductor is a coil conductor or Is a multiplex cylindrical winding characterized by being connected to another shield conductor. 2. The multiple cylindrical winding according to claim 1, wherein the shield conductor is composed of a composite conductor.